The control circuit null of the electric heater which is used for the electric space heater

摘要

PURPOSE:To avoid the danger of employing an electric heating apparatus over a long period of time by controlling the electrification of an electric heater at a temperature lower than the temperature that a temperature-setting means sets when the electric heating apparatus has been employed for more than a set time. CONSTITUTION:A microcomputer 5 writes a counted time data in an integrated electrification time storage device 6 each time the employed time of an electric carpet goes past a set time t0, and when the total of the written time exceeds a certain time t1 the microcomputer lowers a temperature set by a temperature- setting circuit 3 more than a temperature selected by slide resistance 31 in a stepped fashion at the rate of T degrees Centigrade per employed time t2 of the carpet. Then a user thinks that the heating function of an electric heating apparatus has deteriorated, and accordingly stops employing the electric heating apparatus. The danger of employing the electric heating apparatus over a long period of time can thus be avoided to safely terminate the product life of the apparatus.